Sheet separating and feeding mechanism for printing presses



Jun 11, 1940. J. F. ROI-155K 2,203 823 SHEET SEPARATING AND FEEDING MECHANISM FOR PRINTING PRESSES Filed Sept. 21, 1959 2 INVENTOR. J0 sap/r 6? whoa sex? ATTORNEY patented June 11, 1940 SHEET SEPAEATING AND FEEDING MECHA- l N'ISM FOR. PRINTING DRESSES Joseph F. Jirousek, Cleveland, Ohimassignor to The Chandler a Price. Company, Cleveland, Uhima amputation of Ohio Application September 21, 1938, SerialfNo. 231,033 2 Claims. (01. 3 sir-26) This invention relates-,as indicated, to sheet separating and feeding mechanism forprinting presses, but has reference more particularly to mechanism designed for use in association with a printingpress of the character described'in my copending patent application, Serial No. i83,4'76. Although it has heretofore been common practice to direct a blast of air against the forward edge of a stack of sheets to be printed inorder to cause a separation of the uppermost sheets of the stack, to thereby facilitate feeding of the sheets, there is still a tendency,.due to a number of different factors, for the uppermost sheet to adhere to the subjacent sheet, rendering separation diiiicult. l

It is aprimary object of the present invention to provide means for effecting a separation of such uppermost sheet of the stack from the sub-- jacent sheet, soas to facilitate the removal of the uppermost sheetfrom the stack.

Another object of the invention is to provide suction means for removing the sheets from the stack, and for eifectingmovement of such means from and to the stack in predetermined paths,

designed to facilitate the handling of the sheets.

Tothe accomplishment of the foregoing and related ends; saidinvention, then, consists of the means hereinafter fully described and particularly pointed out in the. claims. V

'Ihc annexed drawing and the following descrlptionfset forth in detail certain mechanism embodying the invention, such disclosed means constituting, however, but one of various mechanical forms in which the principle oflthe invention may be. used. i

In said annexed drawing:

Fig. l is a fragmentary plan view of the sheet feeding, mechanism; l

1 Fig. 2 is a cross-sectional view, taken on the line 2---2 of Fig. 1, with the sucker tips intheir rearmost position;

, Fig. 3 is a cross-sectional view, taken on the line3--3 of Fig. l, with the sucker tips in the same positionas in Fig. 2;

Fig. 4 is a View similar toFig. 2, but with the sucker tips in their foremost position} i Fig. 5 is a view similar to Fig. 3, withthe sucker tips in the sameposition as in Fig. 4;

Fig. 6 is a fragmentary cross-sectional view,

takenon theline 6-B,of Fig. 5; and r .7 is a fragmentarycross-sectional view, H

taken on the line !--'I of Fig. 1.

1 Referring more particularly to the drawing,

it may benoted that the present mechanism is designed to replace the sheet feeding mechanism described in my copending patent application,

Serial No. 19,688, so that the latter application may be referred to for a general description of.

the press with which the mechanism is to be associated.

The press, generally considered, has a feed tablewhich supports a stack S of sheets to be I printed, the front guides of the table being designated by, reference numeral I, such front guides rising somewhat above the stack of sheets so as to provide an abutment for the front edges of the sheets. The sheets are individually removed from the stack by means of the sucker tips 2 and are carried by such tips over the upper ends 3 of the front guides l and onto a series of laterally spaced endless tapes 4, driven by rollers, one of which. designated 5,is shown in the drawing. Thesetapes carry the sheet to the feed plate (not shown) of the press. wardlystep by step as the sheets are removed from the top of the stack and suitable mechanism for thus elevating the feed table is described at some length in the aforesaid copending application, Serial No. 19,688. i

In order to hold the sheet on the tapes as it is being transferred to the latter, rolls 6 are pro vided, which overlie the roller iiand function in a manner similar to the rolls 28 in the aforesaid copending application, Serial No. 19,688. These rolls B are mounted on arms I whichare pivctall ly mounted on a cross-shaft frame 9 of the press.

Journalled in the frame 9 of the pressis a driven shaft It; to which are rigidly secured the 8 secured to the various operating cams Ofthe feed mechanism.

Such cams include a pair of spaced forwarding cams ll anda pair of spaced elevating cams l2. Mounted on the shaft Ill,intermediate the cams H and 12, are blocks l3, which form guides 1 for vertically slidable yokes M. The arms of each yoke are bridged by cross-pieces It, the yokes with such pieces, forming in effect, rectangular frames. The blocks [3 are supported against movement axially of or 'pivotally about the shaft Hlby means ofbrackets 16 which are The feed table is fed upsecured to a hollow tube l'l, carried by brackets it, which are secured to the frame 9 of'the press, as by screws l9.

Slidably mounted in the arms of the yokes :4, and with their axes normal to said arms, are

rods 20, which are provided near their forward ends with enlarged knobs 2|. To lateral bosses 22 of these knobs are pivoted links 23, which are pivotally secured at their other end to levers 24.

The levers 24 are. pivoted as at 25, to the yokes l4 and have mounted thereon at points intermediate the ends cam rollers 26. These cam v rollers are maintained in engagement with thecams H due to the action of expansion coil springs 2'1, which are mounted on the rods 20, between the yokes I4 andstop collars 28 on said 1 rods.

v extending arm 3! having a vertical passage in its;

The rods have mounted on their forward ends hangers 29, in the lower ends of which is mounted a tubular member 30. To the central portion of this member is secured a rearwardly rear portion through which a sucker tube 32 extends. This sucker tube is provided at its upper end with a head 33, whichengages-the arm 3| to limit downward movement of the-tube, and is also provided with an expansioncoil spring 34, inter-' posed between the arm 3| and the sucker tip 2, such spring serving to normally maintain the sucker tube in its lowermost position with respect to the arm, but being yield'able to prevent damageto themechanism upon engagement of the sucker tip with the stack of sheets. A flexible tube 35 connects the suction tube It with the head 33 of the sucker tube 32, so as to provide suction in the sucker tip 2 at predetermined intervals.

Secured tothe ends of the member 3B, are

bracketsiil, from which extend rods 38 and? 39 which are parallel with the member, 30. Mounted on therods 38 and 39 are inclined blocks 40 having vertical passages through which sucker tubes 4| extend. These sucker tubes are provided near their upper endswith stop collars 42, which en-' gage the blocks 40 to limit downward movement of the tubes, and are also provided with expansion coil springs 43, interposed between the blocks 50i and the sucker tips 2, and which function in g by the action of compression springs 48, which,

as shown in Fig. 4, interconnect the upperends of i the yokes M with the crossshaft 8.

The yokes I4 are further provided at the rear withbrackets 49, which carry depending rods .50, provided at their lower ends with presser-shoes 5!, the function of which will presently be described.

Having described in detail the construction of the sheet feeding mechanlsm the operation will now be briefly described.

With suction created in the sucker tips 2, such tips are brought to the position shown in dotted lines in Fig. 2, in which position they engage the forward portion of the uppermost sheet of the stack. 7 This portion of the sheet has been elevated somewhat above the upper level of the stack by means'of a blast of air discharged against the forward edges of the stack by the air blast heads B,,such blast being efiectiveto fluffup about six or sevenof the sheets. In-spite of this sheet-separating blast, there is a tendency for the uppermost sheet to stick to the'sub jacent sheet, and in order to separate suchsheets, the forward portion of the uppermost sheet" is caused to slide substantially rearwardly with respect to the forward portion of such subjacent sheet. This is effected by movement of the sucker tips from the dotted to the solid line position in Fig. 2, it being noted that themovement of the tips is slightly downward as well as rearward, this being somewhat more effective than a straight rearward movement. During this movement, which is effected by theconjoint action of the cams H and springs 21, the shoes 5| bear on the stack, as shown in Fig. 2, so as to prevent displacement bodily of the uppermost sheet of the stack.

. The sucker tips are then caused to move upwardly to the dotted line position shown in Fig. 4

and thence forwardly to the solid line position in this figure, in which position, the forward edge of the sheet is entered between the roller 5 and rollers 6 and onto. the sheet conveyor tapes 4.

This upward and forward movement lifts the sheet over the guides 3, and iseffected by the camsllandll g After the sheet enters the roller 5 and rollers 6, the vacuum in the sucker tips is broken and the latter are returned in a rearward and downward path to the dotted line position shown in Fig. 2. Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the mechanism herein disclosed, provided the means statedby any of the following claims or the equivalent of such stated means be employed.

I therefore particularly point, out and distinctly claim as my, invention:

1. In sheet separating and feeding mechanism for printing presses and the like, the combination of sheet conveying means, a feed table adapted to support in a substantially horizontal position a stack of sheets to be fed to said conveying means, presser-shoes operative to bear on the upper surface of such stack, means for directing a blast of air against the forward edges of the uppermost sheets of the stack in order to fluff said sheets, suction means for feeding said sheets individually to said conveying means, and means for imparting to said suction means amovement whereby the forward portion only of the uppermost sheet of the stack is moved rearwardly and downwardly with respect to the forward portion of the subjacent sheet of the stack and is thereafter fed to said sheet conveying means.

2. In sheet separating and feeding mechanism for printing presses and the like, the combination of sheet conveying means, a feed table adapted to support in a substantially horizontal position a stack of sheets to be fed to said conveying means, presser-shoes operative to bear on the upper surface of such stack, means for directing a blast of air against the forward edge of the uppermost sheet in order to fluff said sheet, suction means for feeding said sheets individually to said ,7 conveying means, and means for imparting a .means, presser-shoes operative to bear on the up- 'per'surface ofsuch stack, means for directing a blast of air againstthe forward edge of the uppermost sheet in order to fluff said sheet, suction means for feeding said sheets individually to said conveying means, and means for imparting a movement to said suction means after contact with said uppermost sheet whereby the forward portion only of the uppermost sheet of the stack is moved rearwardly and downwardly with respect to the forward portion of the subjacent sheet of the stack and is thereafter raised and the sheet fed forwardly to said sheet conveying means.

"JOSEPH F. JIROUSEK. 

